1. Field of the Invention
The present invention relates to a network apparatus and related method, and more particularly, to a network apparatus and related method for eliminating interference between transport ports.
2. Description of the Prior Art
A full duplex Ethernet communication of a 1G base-T/10G base-T system is accomplished by four unshielded twisted pairs (UTP). Thus, a transport port can have a plurality of channels, such as four channels. For the most part, the transmitted signals of a channel, (i.e. an unshielded twisted pair), at its transmitter are interfered with by an Echo formed at its receiver, and the transmitted signals of the transmitter are also interfered with by near-end cross talk (NEXT) formed at the other receivers. When processing digital signals of the receivers, the interference must be eliminated. In general, a Least Mean Square (LMS) update FIR canceller can be adopted to eliminate interference in a time domain, or be transferred to a frequency domain to eliminate interference.
In the prior art, however, only the interference within the same transport port (such as the Echo and the NEXT) is considered to require elimination. In practice, a network apparatus, such as a switch, with a plurality of transport ports always encounters interference coming from other transport ports. For example, in order to reduce costs, a transformer of a multi-port switch puts two or four coils of transport ports into the same element. Due to the internal coils of the transformer influencing each other, the adjacent transport ports will interfere with each other to affect signal quality.